Magnet-grouping device for electrical musical instruments.



.I.' F. KELLY.

MAGNET GROUPING DEVICE FbR ELECTRICAL MUSICAL INSTRUME f1! L l wig WITNESSES:

f mm-6% APPLICATION [ILED JUNE 4. I914- Patented Feb. 19, 1918.

IN V EN TOR.

ATTORNEY.

JOHN F. KELLY, 0F PITTSFIELD, MASSACHUSETTS.

MAGNET-GROUPING DEVICE FOR ELECTRICAL MUSICAL INSTRUMENTS.

Specification of Letters Patent.

Patented Feb. 19, 1918.

Continuation of application Serial No. 722,118, filed September 24, 1912. This application filed June 4, 1914.

Serial No.

1 0 all whom it may concern:

Be it known that 1, JOHN F. KELLY, a citizen of the United States of America, residing at Pittsfield, in the county of Berle shire and State of vvMassachusetts, have invented certain new and useful Improvements in Magnet- Grouping Devices for Electrical Musical Instruments, of which the following is a specification.

This invention relates to improvements in magnet grouping devices for electrical musical instruments of the type in which a perforated note or music sheet is employed to control the operation of the electro-magnets of the instrument which, in turn, operate the keys or other devices which cause the tone-producing devices to operate, the present case beinga continuation in part of my allowed application, $01. No. 722,118, filed Sept. 24-, 1912.

An object of the present invention is to provide devices by means of which the total number of circuit closers or circuit-controlling devices of the instrument may be reduced, or, what amounts to the same thing, reducing the number of longitudinal rows of slots or perforations in the note-sheet of a music roll. On. the key-board, for instance, on an eighty-eight note piano, the width of tho note-sheet is objectionable on account of the expense in making it, especially if composed of heavy and. expensive material.

A further object of the present invention is in the provision of devices or means by which the length of the perforations in the note-sheetwhich control the circuit closers of the note-name group may be reduced. By reason of the fact that the perforations in the note-sheet, which controls the operation of the circuit closing devices in the note name group, occur more frequently than. the perforations which cause the individual notes of the instrument to be played, it is desirable that some means he provided to cut down or lessen the length of these pertlorations in order to avoid the objection. of unduly weakening the note-sheet.

further object of the invention is in the provision of devices to cause the key- 0])01'Zitlflg elcctro-magnets to automatically retain their own circuit closed until the termination of the sounding of the tone or note is due. This closure must, therefore, continue or be maintained until after the notename group of circuit controllers have ceased to operate after first closing the circult to the rey-operating magnets, as will be explained in the body of the specification.

I employ a separate or independent connection from one terminal of each of the operating magnets to a common circuit closer, and on the other side or terminal of the operating magnets there is a branch grouping of one or two of those operating magnets of different note-name In order to operate a key-operating nuiguet for causing a note to be sounded, a contact in the circuit of the note-name or larger group is closed, and in this circuit is included the contact corresponding to the smaller grouping. This arrangement or scheme of grouping over the piano scale, as will be fully eX- plained in the body of the specification, cuts out thirty-six of the sharps, and, at the same time, only adds twelve contacts in the larger or note-name group, thus effec ing a saving over the entire scale of twenty-four contacts. Consequently a less number of perforations in the note-sheet is required and therefore a corresponding saving in width in material and expense. This arrangement or scheme of connecting. the operating magnets by grouping them together with separate lines to a common contact prevents the possibility of any cross-connections between the operating magnets and, at the same time, saves electrical energy, on account of the reduction in length of the perforations which control the circuit closers of the notename group.

Referring to the drawings" Figure 1 is a diagrammatic view of the electrical connections for the groupings show ing the separate lines leading to a common circuit closer of the note-name group, also showing the devices to maintain the circuits to the operating magnets of different note name closed until the termination of the n ote; being played is properly due.

Fig. 2 is a view showing the devices for closing and automatically holding the cir' cuit closed to each key-operating magnet: while the note is being played or until the termination of the note being played is due.

Fig. 3 is a detail view showing the arrangement and relative size of the slots in the note-sheet with the two sets of perforations, the smaller ones for controlling the operation of the note-name group and the larger ones for controlling the operation of the individual notes, anc, Fig. i is a detail view illustrating in cross section. the trackerbar and note sheet.

Referring to the drawings in detail, 1, 2, and 3 may be considered as designating the groups of key or other operating magnets which operate the keys of the instrument that cause tones of different note-names to be sounded. In group 1, for instance, the magnets 6 of each of the groups designated 1 may be considered as connected to the keys which effect the sounding of the a note. The magnets 7 of each of the groups designated 1 may be considered as connected to the keys of the instrument which operate the a sharp note. The magnets S of each of the single groups indicated at 2 may be con sidcred as being connected to the keys of the instrument which causes the note Zr to be sounded. The magnets 9 may be considered as connected to the keys which operate the a note, and the magnets 10 the c sharp notes.

Extending from one terminal of each or the key-operating magnets of the several groups indicated at 1, 2, 3, are wires 11, 12, and 13 which terminate at a common relay or circuit-closing device 1%, the movement of the pivoted armature 15 of which simultaneously closes the circuit to each of the wires 11, 12, and 13, the pivot being indicated at 15 This closure may be accomplished by providing the pivotally mounted armature 15 with an extension piece or finger 16. The larger group of circuit closing de vices is designated as a whole by the numeral 17. This group may be termed the note-name group. The operating magnets 7 of each of the groups 1, representing the a sharp notes, each have separate connection 1.8, 19, and 20, which extends to a common relay or circuit closing device 21. In the same manner, a separate connection extends from one terminal of each of the operating magnets to a common circuit closing device or relay indicated at 14, 21 and 29. The opposite terminals of the key-operating magnets 6 and 7, for instance, of the group designated l are connected together at the point 22 to a common wire 23 which leads to a circuit-controlling or closing device 2%, which comprises a perforation in the note-sheet 25 that represents the note that is to be played or sounded.

As the note sheet 25 moves over the tracker bar 33, see Fig. 4, the terminals 23, 30, etc, enter the openings 24 in the tracker bar and closes contact with the conductor 34 which extends through the bar and is electrically connected to the wire 33 which extends to the source of electrical energy.

Then-"ires 26, 27, and 28 separately extend from one terminal of each of the magnets 8 of the 7) natural group to a common circuitcloser 29. In order to avoid confusion,

nesaeoa the opposite terminals 01 the e magnets are not grouped with any of the other operating magnets but are connected by means of a wire 30 directly with a perforation 2% of the note-sheet which represents the 7) natural note in that particular octave.

The battery or other source of electrical energy is indicated at 31, one terminal of which is connected by a wire to a wire 33 which may be considered the tracker-bar terminal of the instrument and also the common connection from one terminal of the battery to the branches 2 3, 30, etc, which serves to connect operating magnets of diil'erent notenames together. The note-sheet etiects the closure of the various circuits in the two sets of groupings of electro-magnets, that to say, the note-name groiiip 17 of the same name and the key-operating group 1, 2, 3, etc., of diiterent note-name. Connected to the other terminal of the battery is a return wire 3st. 35 designates fixed contacts that are connected to the return wire by means of the wires 36 and 37. Connected to the tracker-bar or terminal 33 are wires b8 which serve to close the circuit to any one oi the electro-magnets or relays 11, 21, 29, etc, by means of the wires which cooperate with the short perforations 40 in the note-sheet 25. The other terminals of the electro-magnets 1st, 21, 29, etc., are connected by means of the wires 41 with the wire 37 and this, in turn. to the wire 36 that is connected to the wire 34 that leads to the other terminal of the battery.

Referring now to the devices by means of which each of the circuits to the individual key-operating magnets is automatically maintained closed until the termination of the sounding of the note is due. 42 is an oscillating armature which is connected to the key 13 of the instrument by means of the rod 44. Secured to this armature is an eccentric or cam Attached to a suitable support adjacent; to the poles of the mag);- nets and insulated therefrom and from each other, are the contacts 16 and 17. These are connected by means of the wires 48 and 49 to the wires 37, 11, 18 etc, of each group. That is to say the switch 16 and 17 is located in 'ires 18 and L9 which are in a shunt circuit pa allel to the wires 11, to which the contact 15 is connected. This short circuits th switch 15, 16.

It is further to be understood that the switch 46 and 17 is used on each of the operating magnets in the different groups 1, 2, 3, etc., and that the switch for each operating magnet is connected in the same manner to the various wires, 18, 26, etc. A portion of the perforated note-sheet is indicated in Fig. 3 in which the length of the perforation indicates the time that the note represented thereby is to be played during the movement of the notesheet over the tracker-bar. The

- tions 40 in the noteshcet closes the circuit perforations 40 which are shorter in length are used simply to close the circuit through the relay magnets 14, 21, 29, etc, and, as stated, by making them short the sheet is not weakened. It is evident that in order to cause a note to be sounded that two of the perforations 24 and 40 must simultaneously cooperate.

The operation of the apparatus is as followsFirst, consider that one of the perforafrom one terminal of the battery 31 to the wires 32, 33, 38, perforation 40, and wire 39 to one of the electro-magnets, say 14, depending, of course, upon which one of the perforations is brought into registration with the terminals of the wires 38 and 39. The current then flows to the other terminal of the battery by the wires 41, 37, 36, and 34 back to the other terminal of the battery. At the same time, one of the perforations 24, representing a note to be sounded, in the group 1, for example, of the key-operating electro-magnets will close the circuit through the magnet 6, for example, permitting the current to now flow from the battery 31, wire 32, trackerbar terminal 33, perforation 24, wire 23, to the key-operating electro-magnet 6, for example, wire 11, contact 16, armature 15, contact 15, wires 35, 37, 36, and 34 to the other terminal of the battery 31. In the meantime, the oscillating armature 42, by means of the eccentric or cam 45, has now closed the contacts 46 and 47. During this interval, the short perforations 40 have passed from the terminal wires 38 and 39, but the circuit from the battery is still closed in order to cause the note represented by the perforation 24 to be sounded as long as the perforation 24 registers with the wire 23 and perforation 24 of the tracker-bar terminal 33. The current now flows from the battery 31 by means of the wires 32 and 33, perforation 24, wire 23, the key-operating electro-magnet 6, for example, contacts 46 and 47, wires 37 and 36, back to the other terminal of the battery. Or to state the matter more clearly, it will be seen that the key-actuating magnets will retain their own circuit closed as long as the perforation 24 is in use. Each of the relays or electromagnets 14, 21, and 29 serves merely to close the circuit through the particular key-operating magnets which. in turn, close the contacts 15', for example.

By means of this arrangement or double grouping of the contacts, it will be seen that the number of perforations in the note-sheetis materially reduced. The number of con tacts in the terminals 38 and 39 which corresponds with the number of perforations 40 in the note-sheet in the note-name group 17 will, of course, be 12, namely, from a to g sharp. By combining the naturals with the sharps in the smaller groups 1, 2,

3, etc., as a and a sharp and connecting the two wires 11 and 18 on one side or terminal of the key-operating magnets 6 and 7, as shown at 22, with a common wire 23, a single circuit-closing perforation 24 in the note-sheet will serve to operate either one of the key-operating magnets that effect the sounding of these two notes. This manner of connecting or grouping all of the notes with their sharps, as a and a sharp, over the whole key-bar makes 36 groups each of which contains two key-operating magnet-s, but from this number must be deducted the number twelve given above which is the number of contacts in the note-name group 17. Therefore, the total number of contacts over the whole range of the key-board is reduced by 24. The same grouping can, of course, be made by making a similar group of flats and naturals instead of sharps and naturals, and a still greater saving of space on the note-sheet can be effected by taking the notes in pairs along the scale, but this would be apt to be confusing to the operator when laying out the master-roll.

It is to be understood that the present improvement is not limited to the actuation of the keys as the actuating devices may be directly connected to the action or the devices which cause the tone sounding devices to operate, and it is also obvious that an analogous method such as herein described could be employed embodying the same general principle to operate pneumatic players if so desired.

It will be seen that each one of the operating magnets of a group, as 1, is separately connected to a different relay, and, by reason of this fact, there would not be any danger of any of the other operating magnets being accidentally sounded on account of cross connections between these magnets.

By the terms tone-producing devices or sound-producing devices wherever used in the specification, it is to be understood to refer to the part of the musical instrument which actually emits or produces the mu sical sounds or tones as, for example, the tuned wires of a piano.

Also, wherever the terms circuit closer or circuit controller is used, it is to be understood as referring to a make-and-break device and not to the perforated note-sheet which may be said to control? the circuit.

The term tracker-bar is understood as referring to the element over which. the note sheet drawn during the operation of the instrument.

It is also to be understood that the op-- erating magnets are to be considered as being connected into two groups, as, for example, magnets 6 and 7 in all of the octaves constitute one group, magnets 8 or the 5 natural of each octave another group; and that the operating magnets may, therefore,

be considered as having a double arrangement of groupin What I claim is' 1. An electrically-operated musical instrument, comprising in combination, connections in parallel on one side of the operating magnets to group together said magnets which operate the tone sounding devices of the same notename, a common connection, connections extending from the other terminals of said magnets to the common connection to group together in pairs to the common connection some of said magnets which operate the tone sounding devices of different note-names, a source of electrical energy to the opposite terminals of which said parallel and group connections are connected, a tracker-bar in said latter connections, and a note-sheet coope *ating with the tracker bar for controlling the parallel and group connections.

An electrically operated musical instrument, comprising, in combination, electromagnets to operate the tone producing devices, connections to group together one terminal of each of said magnets for causing the production of tones of the same notename, a circuit closer in each of said connections, a source of electrical energy, connections from the other terminal of each of said magnets to a terminal of the source of electrical energy, a circuit controller in each of said last mentioned connections, some of the latter connections serving to connect together magnets which operate tone-producing devices of differentnote-names, and connections from the other terminal of the source of energy to the first-mentioned connections, a tracker bar in said connections, and a note sheet cooperating with the bar for controlling the connections.

3. An electrically operated musical instrument, comprising in combination, operating magnets, connections from one terminal of each of said magnets for grouping said magnets together which operate tone-producing devices of the same note-name, circuit closers for said connections, a source of electricalenergy, one terminal of which is connected to said Conn 'ctions, a plurality of said magnets each having its other terminal connected to a separate connection, a trackerbar, terminals therein to which each of the last named connections is connected, and connections from the terminals of the tracker-bar to the other terminal of the source of electrical energy, said tracker-bar having a less number of terminalsthan the number of operating magnets, whereby a note-sheetformed with a number of perforations that is less than the number of tone sounding devices may be used to control the operation of all of the operating magnets.

&; An electrically'operated musical instru-' ment, comprising in combination, electromagnetic operating devices for operating the sound producing devices, a source of electrical energy, connections from one terminal of each of said operating devices to the source for grouping said devices together which produce tones of the same note-name, a contact in each of said connections, an electromagnet to operate each of said contacts, con nections from the source to one terminal of each of the contact operating electro-magnets, connections from the other terminal of the contact operating electro-magncts to the other terminal of the source, connections from the opposite terminal of each of said first named operating devices to the source for grouping a plurality of the electro-magnetic operating devices together which operate tone producing devices of different note-name, a tracker-bar having the terminals therein included in the last mentioned connections, the number of terminals in the tracker-bar being less than the number of tone-producing devices, and a perforated note-sheet to engage the tracker-bar as described.

53. In an electrically operated musical instrument, the combination, of elcctro-magnets, armaturcs therefor, connecting means between the armatures and the tone producing devices for operating the tone-producing devices, a source of electrical energy, connections from the terminals of the magnets to the terminals of the source of energy, a circuit closing device in each of said connections, means for ope 'ating said closing device in each connection, and means operated by the electro-magnets for maintaining the circuit closing devices in said connections closed during the periods which correspond with the notes of difierent length, as described.

6. In an electrically operated musical instrument, the combination, of electromagnets, armaturcs ope "ated thereby for operating the tone-producing devices of the instrument, a source of electrical energy, independent conncctions from the terminals of said magnets to the terminals of the source of energy to group said magnets together which produce tones of the same note name, a circuit closing device in each of said connections, the circuit closing devices in said connections being operated by the movements of the armatures of the electro-mag nets for maintaining the circuit closed to that particular electro-magnet during the operation of the tone producing device.

7. In an electrically-operated musical instru'ment, the combination, of operating magnets for actuating the tone producing devices of the instrument, a source of electrical energy, means extending from one terminal of the source of electrical energy to electrically connect the operating magnets together which operate tone-producing devices of the same note-name, a circuit closer in each of said connecting means, an electromagnet to operate the circuit closer, separate means to electrically connect together some of the operating magnets which actuate tone-producing devices of different notename, a common terminal to which the lastmentioned connecting means is connected, at tracker-bar to which the common terminals are connected, a make-and-break device in said last named connection for controlling the operating magnets, the number of terminals in the tracker bar being less than the number of operating magnets, whereby a note-sheet having a number of longitudinal rows of perforations that is less than the number of operating magnets may be used to control the operation of all of the tone producing devices of the instrument, as described.

8. In an electrically operated musical instrument, the combination, of operating magnets, connections from one terminal of said magnets to group together said magnets which operate tone-producing devices of the same note-name, a circuit closer in each of said connections, means controlled by the note-sheet to operate the circuit closers, connections from the opposite terminals of each of the operating magnets to group together some of the operating magnets which operate tone-producing devices of different notenames, a connection from one terminal of each of the magnets to the source of electrical energy, a circuit closer in the last named connection and independently operated by each individual operating magnet for holding the circuit closed through that particular operating magnet for a time corresponding with the length of perforation in the note-sheet which represents the time the note is to be played, a source of electrical energy, a tracker-bar, terminals therein to Which the connections from the opposite terminals of the operating magnets extend and connections from the tracker-bar terminals to the terminals of the source of electrical energy, the number of terminals in the tracker-bar being less than the number of operating magnets.

9. In an electrically operated musical instrument, the combination, of operating magnets, electro-magnetic make-and-break devices, connections extending from the terminals at one end of said magnets to the make-and-break devices for grouping those magnets together which cause the produc tion of tones of the same note-name, a source of electrical energy, connections from the source to the terminals of the said make-andbreak devices, connections extending from some of the opposite terminals of saidmagnets to the source for grouping together the operating magnets which cause the production of tones of differentnote-names, a

tracker-bar, terminals therein and connected to the last named connections, and means including a perforated note-sheet cooperating with the terminals in the tracker-bar and the last named connections for opening and closing the connections to said make-andbreak devices, and for opening and closing the connections from the opposite terminals of said magnets which connect together operating magnets of different note names.

10. In a musical instrument, the combina tion, of operating devices, a source of electrical energy, means to group said devices together which cause the production of tones of the same note-name, means to group together a plurality of said devices which cause the production of tones of different note-names, means including a tracker-bar and note-sheet for controlling the operation of said grouping means for energizing any individual operating device, as described.

11. In a musical instrument, the combination of electromagnetic operating devices, a source of electrical energy, a perforated note-sheet controlling said devices, connecting means from the terminals on one side of said operating devices to one terminal of the source of energy for groupin together said devices which cause the production of tones of the same note name, connections on the other side of some of said devices to the other terminal of the source of energy for grouping together devices which cause the production of tones of difierent note names, a common connection from one terminal of the source of energy, a branch connection from each of the first mentioned terminals on one side of said operating means to the common connection, a make and break device in each one of said branches controlled by the note-sheet.

12. In an electrically operated musical instrument, electro-magnets, armatures therefor, connecting devices from the armatures for actuating the sound-producing devices of the instrument, a source of electrical energy, connections therefrom to the terminals of the electro-magnets, make-and-break devices in said connections, connections from each of the same terminals of the electromagnets to the source of electrical energy, a make-and-break device in each of the last named connections, means operated by the movements of the armatures to operate the made-and-break devices in said last-named connections, connections extending from each of the other terminals of the electromagnets to the source of electrical energy, a tracker bar in the connections, and a perforated notesheet cooperating with the tracker-bar for controlling the operation of all of the make-and-break devices.

13. An electrically-operated musical instrument, comprising, in combination, operating magnets, connections from one side of all of the magnets to group said magnets together which operate tone-sounding de vices or the same note-name, connections from the other side of some of the magnets to connect a plurality of said magnets together which operate tonesounding devices of different note-name, circuit closers in all of said connections, a single source of elec trical energy, and to which the connections are connected.

1%. An electrically-operated musical instrument comprising, in combination, electroana netic devices for operating the sound-producing means. a source of electrical energy, connections from one terminal of each of said devices to the source of e1ectrical energy for grouping said devices together which produce tones of the same notename, a contact in each connection, an electro-magnet to operate each contact, a tracker-bar, terminals therein, a connection from one terminal of each of the contact operating electro-magnets to separate terminals in the tracker-bar, a connection from the terminals of the tracker-bar to the source of electrical energy, a connection from the other terminal of each of the contact operating electro-magnets to the other terminal of the source of electrical energy, connections from some of the opposite terminals of said operating devices to terminals in the tracker-bar for grouping a plurality of electro-magnetic devices together which operate the sounding devices of different note-name, a connection from said last mentioned terminals to the source of energy, said tracker-bar having a less number of terminals therein than the number of said sound producing devices, a note-sheet engaging the tracker-bar for closing the terminal connections therein, whereby the connec tions to said sound producing devices may be operated.

15'. In an electrically operated musical instrument, the combination, or operating magnets, a single source of electrical energy, connections extending from the terminals of said magnets to the terminals of the source of electrical energy for electrically connecting said magnets together into a double grouping arrangement, a circuit closer comprising a note-sheet in the connection of each group, one of said grouping connections serving to sound tones of the same note name and the other grouping connections serving to sound tones of different note-names, as described.

16. In an electrically-operated musical instrument, the combination, of operating magnets, armaturcs therefor, connecting means from the armatures for operating the sound producing means of the instrument, a source of electrical energy, connections extending from the terminals of each of the operating magnets to a terminal of the source for grouping said magnets which op crate the tone sounding devices of the same note-name, make-andbreak devices in the connections, connections from the other terminals of the operating magnets to the other terminal of the source grouping said magnets together which operate tone sounding devices of different note-name, a tracker-bar, terminal therein and included in the connections and a perforated note-sheet en aging the tracker-bar and cooperating with the terminals for causing the closure of the connections from the source of electrical en ergy to the operating magnets.

17. An electrically-operated musical instrument comprising in combination, a source of electrical energy, electro-maguetic actuating devices which operate the tone producing devices, connections from one ter minal of each of said actuating devices to the source electrically connecting said actuating devices together which sound tones of the same note-name, circuit closers for the connections, connections from some oi the other terminals of said devices to the source electrically connecting some of said devices together which sound tones of different notename, a tracker bar and note sheet interposed in said last-named connections to control the operation of said devices, and means controlled by the tracker bar and note sheet controlling the circuit closers for the first mentioned connections.

18. An electrically-operated musical instrument, comprising, in combination, electro-magnets to operate the tone-sounding devices, a single source of electrical energy, connections extending from one of the terminals of the electro-magnets to the source of electrical energy to group together said magnets which sound tones of the same notename, circuit closers in said connections, connections extending from some of the other terminals of said magnets to the other terminal of the source of electrical energy,

circuit closers in said latter connections, the latter connections serving to group together said electro-magnets which sound tones of different note-name.

19. An electrically-operated musical instrument comprising in combination, a source of electrical energy, operating magnets, connections from one of the terminals of each of said magnets to a terminal of the source of electrical energy for grouping the same together which operate tone-sounding devices of the same note-name, circuit closers in said connections, a plurality of said magnets having their other terminals connected for grouping said last mentioned magnets together which operate tone-sounding devices of different note-name, circuit closers in said last mentioned connections, a tracker bar having terminals therein of less number than the number of tone-sounding devices of the instrument, some of said terminals in the tracker bar being connected to the connections extending from said other terminals, and other connections from the terminals in the tracker bar extending to the other terminal of the source of electrical energy.

20. A11 electrically-operated musical instrument, comprising in combination, elec tro-magnetic devices to operate the sound producing means, a source of electrical energy, connections from one terminal of each of said devices to one terminal of the source for grouping said devices together which produce tones of the same note-name, a contact in each of said connections, electro-magnets to operate the contacts and connections therefrom to the source of electrical energy, a tracker bar, terminals therein, a connection from the source to the terminals of the tracker bar, connections from some of the opposite terminals of said operating devices to the tracker bar for grouping said devices together which produce tones of different note-name, the tracker bar having a less number of terminals than the number of the sound producing devices, and a note sheet to engage the tracker-bar for closing the circuits to said operating devices and to the contact operating electro-magnets.

21. An electrically-operated musical instrument, comprising, in combination, operating magnets, connections from one side of the magnets to group together said magnets which operate tone-sounding devices of the same note-name, connections from the other side of the magnets to group together a plurality of said magnets which operate tone-sounding devices of different notename, circuit closers in said connections, a source of electrical energy to which said connections are connected, a tracker bar, terminals therein which are included in the connections from said other side of the magnets and a note sheet cooperating with the tracker-bar and having a less number of longitudinal rows of perforations therein than the number of operating magnets.

JOHN F. KELLY.

Witnesses:

HELEN T. KELLY, J. E. KELLY.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

Washington, D. 0." 

